


No I In Threesome

by cptxrogers



Category: Avengers Assemble (Cartoon)
Genre: Blow Jobs, Bottom Tony Stark, Dubious Science, Explicit Sexual Content, Fluff and Smut, Inspired by Fanart, M/M, Reverse Big Bang Challenge, Smut, Spitroasting, Threesome - M/M/M, one Tony two Steves
Language: English
Status: Completed
Published: 2019-05-19
Updated: 2019-05-19
Packaged: 2020-03-08 01:46:51
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 8,950
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18885613
Author URL: https://archiveofourown.org/users/cptxrogers/pseuds/cptxrogers
Summary: An accident in Tony's workshop results in an unexpected visitor - a doppelganger of Steve from another dimension.Now Tony is stuck with TWO Steves to handle. Whatever will he do?





	No I In Threesome

**Author's Note:**

  * For [marumo](https://archiveofourown.org/users/marumo/gifts).
  * Inspired by [As You Dreamed](https://archiveofourown.org/works/18880582) by [marumo](https://archiveofourown.org/users/marumo/pseuds/marumo). 



>   
> 
> 
> This fic was written for the Cap-IM Reverse Big Bang 2019. I was so lucky to work with Maru for my first RBB. She was a great partner and I had a ton of fun writing for her wonderful art! She is a delight to have in AA fandom so I was thrilled to write her some smut :D
> 
> Go check out [the art](https://archiveofourown.org/works/18880582) and tell Maru how great it is.
> 
> There's also a second fic for this art by the brilliant [Navaan](https://archiveofourown.org/works/18883954) which you should check out too!
> 
> Finally, I want to thank Mireille for doing sterling work as a beta.

_“There’s no such thing as perpetual motion, Tony.”_

_“Energy cannot be created or destroyed, Tony.”_

People never stop harping on at him about the apparently immutable laws of the physical universe.

But they’re thinking too small. Tony has never been held back by such concerns as common sense or a realistic view of his own abilities.

Everyone needs power, that’s the problem. Tony needs to power his suit, the Avengers need to power the Quinjet’s shields, and the entire human race needs a source of renewable energy that won’t pollute the planet.

So Tony has a plan.

Perhaps energy can’t be created in _this_ universe, but he thinks he can maybe pull energy from _another_ universe. Zero-point energy, that’s the dream. Extracting power directly from subspace, creating a self-sustaining loop which holds the subspace bridge open. In theory, it would mean infinite clean energy for everyone.

It’s the ideal project for a rare weekend off.

He’s been tinkering with the design on and off for months, and this is the first time he’s produced something approaching a working prototype. The device is squat, about the size of a shoebox, and frankly rather unimpressive to behold. But the potential! Tony bounces on the balls of his feet with excitement at the possibility.

From his spot on the couch in the corner, Steve glances up from his sketches. He narrows his eyes as Tony bustles around connecting the last few cables, but he’s learned not to ask Tony too many questions about his projects unless he wants a physics lecture.

Tony takes a breath, readies his sensors to take readings, and flicks a switch.

There’s a pop, and the air around him crackles like static electricity. The device he’s working on shakes and rattles, components jiggling with energy. He looks around quickly; there’s no sign of danger yet, but he doesn’t like the way the device is shaking. He moves toward the emergency override switch, reaching to shut it off -

And then Steve is there by his side, shield in hand as if he could ward off scientific disaster through the sheer power of his stubbornness. “Steve!” Tony yells, moving away from the override switch and grabbing for Steve’s wrist instead.

“No! Stay behind me,” Steve orders, in one hundred percent Captain America mode. He’s eyeing the device as if he could glare it into submission. It’s getting more energetic, to the point that it’s shaking the table now.

Tony loves Steve, he really does, with all his heart. But the man can be a stubborn idiot at times - and it looks like this is going to be one of those times.

“C’mon, Steve, let me adjust it.” Tony doesn’t want to know what will happen if that device explodes, and he certainly doesn’t want Steve to be in front of it.

“Not a chance,” Steve says firmly. “It’s dangerous. I’m not letting you anywhere near it.”

Tony rolls his eyes but is secretly touched by Steve’s concern. He’s still not wild about this plan of using Steve as a human shield, though. “I can turn it off -” he begins.

“I’ll do it,” Steve says, chin tilted up in that way that means he’s ready to fight the entire world if he has to. “It’s that switch on the side, right?”

Steve keeps the shield in place with his right hand and steps forward toward the device with his left arm outstretched.

“Wait,” Tony tries to warn him, but he’s too late. “I need to disable the phase arrays -” He sees it in slow motion: Steve leaning away from him, fingers reaching out toward the device, a fork of blue energy zapping out of it and towards him.

The energy hits Steve’s fingertips with a tremendous crack, and the smell of ozone fills the room, sharp and pungent. Every light and electronic device in the workshop pops and darkens, and Tony can only fumble blindly in the sudden darkness.

“Steve!” he yells, panic seeping into his voice. Horrifying visions fill his mind as he stumbles forward, hands desperately searching for Steve.

“Tony,” Steve answers, and he’s close by, and he doesn’t sound injured. Tony’s hammering pulse kicks down a few notches. “I’m here.”

“Um.” A third voice carries through the pitch black. It sounds oddly like Steve. “And I’m here too.”

Tony’s eyes still haven’t adjusted to the darkness, but he throws himself forward toward the sound of Steve’s voice. He sighs with relief when he hits a familiar wall of muscle.

Steve’s arms slide around him and Tony clings on tight. His eyes are getting used to the dark, and he can make out a dark shape on the far side of the device. The way Steve is tense next to him lets him know that he’s seen it too.

“Who are you?” Steve challenges, all firm confidence.

“I was going to ask you the same,” the voice says, and it really does sound awfully like Steve.

Finally, the workshop’s backup power generator kicks in, and the emergency lights turn on, low and red.

Tony stares at the intruder in his lab, rubs his eyes, and stares some more.

He looks at Steve, who appears even more perturbed than he is.

Opposite them, looking a little sheepish and a lot confused, is a perfect doppelganger of Steve.

 

* * *

 

Steve blinks. Once, twice, three times.

The _other_ Steve is still there.

He looks exactly like him, but it’s not like looking in a mirror. A mirror shows your opposite, whereas looking at this Steve must be how he appears to other people.

They have identical uniforms and identical faces. Their hair parts in the same place. Steve is aware that the other is regarding him with a quizzical gaze, a hint of suspicion behind it.

Steve realizes the exact same expression is on his face.

He reaches out, slowly and deliberately, and pokes the other Steve in the chest.

He seems solid enough, and the corners of his mouth pull down into a familiar scowl as he bats Steve’s hand away. It’s the same expression Steve knows crosses his own face when Clint uses him as target practice.

 

* * *

 

It takes Tony longer than he would like to admit to notice the antiparticle radiation that predated the arrival of other Steve.

He’d like to think that his grasp of interdimensional physics was better than average, but he’s too slow in checking the tower’s automated recordings for energy-related anomalies.

He is, frankly, distracted.

The conversation between the three of them is stilted and awkward. Other Steve insists that he has no idea how he traveled here or what happened, and Tony and his Steve are naturally suspicious.

There’s a frisson of worry that the other Steve could be an impostor or have malicious intention. Then there’s a feeling of guilt that if he’s not, this poor Steve is far from home, and somewhere out there is another version of Tony who’s probably going out of his mind with worry.

And then there’s the base part of his libido which can’t stop thinking about all the things he could get up to with _two Steves_. He tries to ignore that part and focus on the physics problem.

Once he finally thinks to pull up graphs showing records of the energy sensors in the workshop, it’s clear as day: a spike of antiquarks in the milliseconds before other Steve appeared. Wherever this Steve came from, it wasn’t magic or a trick; it was science.

Tony nods decisively. “A parallel universe,” he says. This, at least, he can understand.

“The zero-point device must have activated when you touched it, Steve,” he muses. “It connected to your parallel universe counterpart and rematerialised him here. Let me check if the phase arrays detected any anomalous readings…”

He gets to work, puzzling out the rational scientific explanation for what was going on.

 

* * *

 

Tony has that glazed, far away look on his face that Steve recognizes as his “deep in science thoughts” face. He knows better than to interrupt him or try to engage him in conversation when he looks like that.

Instead, he motions the other Steve over to the raggedy old sofa in the corner and sits him down to talk.

Tony bangs around the workshop muttering to himself and collecting tools as the Steves huddle in the corner. Steve finds it strange, at first, talking to someone who is so like him. It’s uncanny.

They establish that other Steve is from a world very like this one, that he’d been getting ready for his afternoon training session when he was suddenly pulled into this dimension, and that he has absolutely no idea how it happened.

Steve is still suspicious. It could be a trick, and it seems like the kind of thing Loki would do for his own amusement.

But then other Steve talks about growing up in Brooklyn, about how he’d passed through Park Slope recently and had to pick his jaw up off the floor when he saw the price of a house there. How he’d remembered playing in the street there what felt like not so long ago, joining the neighborhood kids for games of jacks while Mrs. Thrushpot tried to chase them away with a broom.

Steve duck his head and smiles. She had been a Mrs. Thruffrot in his universe, but he remembered her well.

They try to pick out other details where their lives diverge. Steve had fought in the 102nd Infantry Division in the war; other Steve had fought in the 104th. They both loved to paint, but Steve was self-taught and other Steve had been to art school for a time, though he’d said it was not nearly as much fun as he’d imagined it would be. And the Wasp in other Steve’s universe was a woman called Jan, not Hope.

“I’m sure some things are the same in every universe, though,” other Steve says, glancing over at Tony who was currently engaged in provoking a tube of purple plasma with a welding torch.

He must miss his team, Steve realizes. If Steve were transported to another universe, he’d be feeling lost without his friends too.

“Try not to worry,” Steve says, recognizing the crinkles forming on other Steve’s brow. “We’ll do our best to get you home soon.”

Other Steve nods, slowly, but he doesn’t say anything, and Steve feels like that speaks volumes.

He keeps talking, mostly to fill the silence. “Although when I say ‘we’,” he says, tilting his head to the side with a soft smile, “I mostly mean Tony. He’s the one who’s the genius with all this science stuff.”

Other Steve perks up at that, looking from under his lashes over at Tony working.

“I suppose your Tony is a genius too?” Steve inquires.

Other Steve goes a tiny bit flushed. “ _My_ Tony,” he says, mostly to himself. “Yeah, my Tony is a genius all right.”

Steve grins, heart warmed with pride. Adoring Tony Stark was apparently something that all the versions of Steve Rogers had in common across every universe.

Steve looks down at his hand and runs a finger across his wedding band. It’s still amazing to him that he landed literally the best man in the entire world as his husband.

Other Steve looks down too, eyes going wide for a moment. Then he quickly looks away, as if he’s embarrassed to have been caught staring.

“Are you and your Tony not married yet?” he asks conversationally. Perhaps they could go through wedding plans together. At least he could give other Steve some advance warning of the drama that went down at his own wedding. It would be nice if at least one version of Steve and Tony could get hitched without the Cabal gatecrashing and trying to take hostages.

“Oh. No. It’s… it’s not like that,” other Steve says. He looks awkward, shifty, like he’s trying to hide something. Steve knows it because he’s a terrible liar too.

“Did something happen between you two?” Steve asks, horrified by the possibilities. There was that dark time when he and Tony had fought and they’d spilt the team. In their case, they’d made up quickly, but perhaps in another universe they hadn’t. What a terrible thought.

“No,” other Steve says morosely. “Nothing ever happened between us at all.” He looks down at his lap, the tips of his ears reddening.

“Oh,” says Steve as realization dawns. “You never told him how you feel?”

“I meant to. So many times, I wanted to. But it never seemed like the right time. We were always so busy with the team and with missions.”

Steve nods sympathetically. He remembers those times, obsessing over how to tell Tony about his feelings but never finding a moment to themselves. He wasn’t at his best then.

“And…” other Steve looks back at Tony, who’s now futzing around with what appears to be a jar of glowing gas and some kind of electric powered screwdriver. “I’m not sure he feels the same way.”

Steve considers all the ways in which their parallel universes are similar and decides that’s unlikely. But he puts a comforting hand on other Steve’s shoulder all the same.

“I don’t know if I could ever deserve him,” other Steve says, ever so quietly. “He’s hands down the best person I’ve ever met. He’s so smart, and so kind, and he runs his company and helps out at orphanages and builds all of the gear for the team. What’s a man like that going to want with an old soldier like me?”

Steve can’t help but take pity on him. When other Steve talks about his Tony, his eyes light up and he can’t hide his smile. It’s adorable, really.

As they talk, Steve catches himself wondering if _he_ was that obvious when he was mooning over his Tony. And then he thinks about the looks on their team’s faces when they had finally revealed the big secret that they were dating.

He still remembers Natasha’s eyebrow, raised to a single sharp point like an accent. “You don’t say,” she’d said, voice utterly flat. “I’m shocked.” The rest of the team had held firm for about two seconds before collapsing into laughter and congratulations.

So yeah, Steve has some idea how other Steve is feeling. It really is hard not to feel sympathy with a version of himself who’s so obviously lonely and in need of help.

 

* * *

 

There’s a bang and a fizzle, and a spark leaps out of the machine Tony is working on and singes his eyebrow. He jumps back, and both Steves are already on their feet and coming to his aid.

He pats the afflicted eyebrow and checks there’s no permanent damage. “I’m fine,” he assures the Steves. “And good news! The phase shifting modular array is finished!”

A look of relief sweeps across both Steves’ faces. “So I can go home?” other Steve asks.

“Oh. Ahh. Not quite yet.” Tony feels bashful. “The array needs to build up enough zero-point charge to open an interdimensional window. And that will take…” he checks his watch, “approximately 24 hours. Sorry.”

But other Steve is beaming at him. “Don’t apologise,” he says warmly. “That’s amazing, that you could design and build that so fast. You’re amazing.”

Tony feels his cheeks heating at the complement. “It was pretty much my fault that you got stuck here, so I’m glad I can undo the damage. I’d hate to deprive any universe of their beloved Captain, and I’m sure your Tony is worrying himself silly and can’t wait to have you back.”

Other Steve positively glows at that. Tony surreptitiously glances at his Steve, worried he won’t like the two of them flirting. But Steve is smiling, broad and a little bit mischievous, like he’s enjoying watching them.

Huh.

“24 hours?” Steve says thoughtfully. “I suppose we’ll have to find him somewhere to sleep then.” Steve says it all with a look of supreme innocence, but there’s a glint in his eye that Tony catches immediately.

A range of specular and filthy images parade through Tony’s mind. Two Steves. One of him. The possibilities are endless, and most intriguing.

“I suppose we will,” Tony says, rounding on other Steve with a wicked grin. “We wouldn’t want him to be lonely while he visits our dimension.”

Other Steve’s eyes go wide, flicking back and forth between the two of them. He swallows visibly.

“Gosh,” he says.

 

* * *

 

They stop to make dinner for their guest before all three of them end up in Steve and Tony’s bedroom together. Let it never be said they aren’t consummately polite hosts.

Steve shuts the door behind him as he enters, and other Steve regards him thoughtfully. Other Steve taps a finger on his chin and narrows his eyes.

He knows exactly what’s going through other Steve’s head, because it’s what’s going through his as well: Uncertainty at first, a little shyness, rapidly being overridden by curiosity and a spike of lust at the idea of what they could do.

They both turn to look at Tony, who looks a little dazed under the spotlight of both of their gazes. Steve feels a smile tugging at the corner of his mouth. His husband is an endless delight - suggesting a threesome then blushing so prettily when it actually happens. Steve really does love him wholeheartedly.

He can’t help it. He steps towards Tony, puts an arm and his waist and tugs him close, and kisses him hot and messy. Tony melts against him, like he always does when Steve kisses him like that, like it’s the first time all over again.

They pull apart, and Steve is smiling all over, feeling like the luckiest man alive. He remembers their guest and turns to other Steve, whose mouth has fallen into a round little _o_ of astonishment.

Steve motions other Steve over to join them, and he sways for a moment before hurrying over so fast he nearly trips over his boots. He’s all bumbling enthusiasm and furtive glances, and it makes Steve feel young again to see that look on a face so like his own.

Steve graciously steps aside to let other Steve stroke Tony’s face, holding him like he’s precious. For his part, Tony is positively glowing under the attention. Other Steve kisses him on the cheek, ever so delicately, and Tony nearly swoons. He’s such a romantic at heart.

He stands behind Tony, arms around his waist, letting other Steve kiss and caress as he wants. When Steve bends his head to kiss up Tony’s neck, right where he knows Tony loves it, Tony shudders between them two of them in a most gratifying manner.

“More?” he asks softly in Tony’s ear, not wanting to push. But Tony is nodding, gasping affirmatives, apparently more into this idea that Steve would have thought. Threesomes with two of him are apparently Tony’s ideal fantasy. That is so sweet.

He slides a hand under Tony’s shirt, pushing up the fabric while other Steve holds Tony’s jaw and kisses him delicately.

As they move together in one heated clumsy mass Steve feels a building coil of warmth and affection twirling deep in his gut. That an accident of physics should have brought the three of them into contact; that they should be here and experience this together seems like a truly special gift the universe has bestowed on them all.

Somehow the three of them make it across the room, trailing boots and shirts and pinged buttons as they go, falling onto the bed in a pile of joyous laughter.

 

* * *

 

Tony leans back on the bed, fingers twining into the sheets. His heart is thumping fast, and it could be either anticipation or nervousness, he’s not quite sure.

It’s strange that he should be nervous. He loves Steve, he adores Steve, he feels more comfortable and more himself around Steve than anyone he’s ever met.

And the thought of having not one Steve but two of them, all to himself. Well, that’s quite literally a dream come true. But still, he fidgets.

As the other Steve nearly stumbles when he bends to take off his boots, it’s clear that he’s nervous too.

Luckily for both of them they have Tony’s Steve, solid as a rock. He looks Tony up and down and his burrows furrow slightly when he takes in Tony’s hands tensing on the bed sheets. He tosses aside his uniform shirt, leaving just the tight white undershirt that Tony enjoys so much, and comes to sit by him on the bed.

“You good?” Steve asks, all smiles and radiating fondness.

“‘M good,” Tony breathes, trying to relax, eyeing other Steve who is shifting his weight from one foot to the other, looking like he’s trying to decide whether he should take his pants off.

Tony’s Steve rearranges them on the bed until he’s sat with his back against the headboard and Tony is tucked between his legs, his back pressed to Steve’s chest. It’s awfully nice to be surrounded by a cocoon of Steve, firm and smelling faintly of that old-fashioned soap he still uses.

Steve’s arms go around Tony’s waist and his head props on Tony’s shoulder. “Just you and me,” he murmurs into Tony’s neck.

Other Steve raises an eyebrow in mock offense.

“Just you and me and other me,” his Steve corrects, and Tony can feel his smile against his neck.

Tony feels himself relax, letting go of expectations. For once there was no mission or imminent disaster: There was just him and Steve… and other Steve.

“We can do whatever you want,” other Steve offers with a familiar kindness. “Or nothing at all.”

But Tony knows what he wants, and he’s not about to let this opportunity pass him by. He beckons other Steve over to join them, feeling almost shy.

He needn’t have worried, though, because other Steve bounds on over like this is everything he wants. He flops onto the bed with uncharacteristic clumsiness that makes all three of them laugh.

Between Tony and two broadly muscled super soldiers, the bed is pretty cramped. But Tony’s sure not complaining.

 

* * *

 

Steve is enjoying the view immensely.

He’s wrapped around Tony, one of his favorite places to be. And he gets to watch as Tony tentatively reaches out to pull other Steve in for a kiss.

He likes watching more than he would have anticipated. There’s something voyeuristically thrilling about watching intimacy unfold, seeing how Tony’s hands grasp at other Steve’s shirt and how other Steve’s eyes go wide with wonder when Tony kisses him with messy enthusiasm.

And there’s a little part of him that feels a warm, possessive smugness at seeing Tony throwing himself into the arms of, well, him.

Tony pulls back and other Steve gazes at him, eyes lidded and pleasure-drunk. It’s funny, that’s not an expression Steve ever sees on his own face. Whenever he catches a glimpse of himself in a mirror his face appears set and determined, almost grim.

But now, looking at other Steve, he sees himself as Tony must see him: softer, warmer, willing to be led anywhere by Tony.

It’s a good look on him.

“He’s really something, isn't he?” he asks other Steve, curling around Tony adoringly.

Other Steve looks dazed, like he’s still processing the reality of TONY and KISSING TONY and I GET TO KISS TONY. Steve remembers that feeling well.

When he and Tony had talked about it, and they both agreed that they wanted to give other Steve the option to be with them. At first, Steve had been thinking about it as a sort of act of charity, a way of sharing what he was so lucky to have with another version of himself that wasn’t so fortunate.

But seeing how into the idea Tony was, he’d started to see this as an opportunity for them as well. For the two of them to be together, along with someone else. Steve had never considered the idea before, but he is undeniably intrigued.

He wants this for other Steve, wants him to get to experience the wonders of Tony Stark first hand so he might finally have the courage to ask out his own Tony.

And he wants this for Tony, whose heart he can feel pounding against his chest and whose breath is coming in hard pants and who is occasionally looking around like he can’t entirely believe this is happening.

And he wants this for himself, filled as he is with a glowing, possessive warmth that is spreading throughout his body and making him achingly hard.

 

* * *

 

Tony falls into a dreamlike state: the warmth of two bodies pressed against his own, two hearts beating firm and steady, two pair of lips hungry for kisses, trailing everywhere across his skin.

For once, he stops thinking. It’s Steve, and he knows Steve down to his core, and he trusts him, and he loves him in every universe.

The three of them shuck off the last of their clothes, and then there’s the delicious throbbing heat of warm skin surrounding him everywhere. He runs his fingers up other Steve’s arm, delighted by the way Steve blushes and squirms from this simple touch.

His Steve holds him close: secure, familiar, his anchor in any storm.

The Steves seem content to kiss, to touch, to explore. Being the focus of both of them is flattering and enticing in equal measure, seeing the delight on both of their faces as one traces the lengths of his legs and the other mouths at the hollow of his throat.

At one point, other Steve reaches a hand to brush Steve's cheek, and the two of them kiss delicately while Tony's jaw drops. The sight of two Steve kissing is more than he can process, and his brain turns to much. "Hebleugh," he says, cogently, and the Steves pull back from each other and laugh.

He can feel his Steve hard and ready behind him, and he can see for himself just how much other Steve is enjoying the evening so far. But neither of them are in a hurry as they turn their focus back on him.

He jiggles impatiently. This is delightful, but he wants _more_.

“C’mon,” he mutters to his Steve. “Let’s get to the action.”

He pouts and Steve laughs, light and joyful.

“So demanding,” Steve says, and it’s suffused with warmth.

Tony doesn’t care to respond, because Steve is _finally_ wrapping a hand around his cock. His hands are big and soft, with light calluses where he holds his shield. Tony knows every line of those hands, has felt them on his body a thousand times.

He wonders if other Steve has the same calluses. He’ll find out soon enough. For now, other Steve sits back on his heels and stares, drinking in the view.

Steve jerks Tony with firm, confident strokes. His other hand wraps around Tony’s chest, pulling their bodies tighter together until there’s not a millimeter of space between them.

Tony feels himself unwind, feels the tension ebbing away, feels waves of pleasure rolling down his limbs and up to his head, making him lightheaded. Steve’s touch always has that effect on him.

He realizes he’s making little humming noises of pleasure. They’ve barely gotten started, and he’s already feeling so good. He scrunches up his eyes and loses himself in the feeling.

When he opens his eyes again, his gaze meets other Steve’s.

“Oh, _Tony_ ,” other Steve breathes, like he’s having a borderline religious experience.

Tony smiles at him, warm and lazy and content. He waves him over, and other Steve shuffles closer, looked enraptured.

“Kiss me,” Tony suggests, floating warm and content in Steve’s arms.

Other Steve does, gently at first, then with increasing enthusiasm.

Sandwiched between the two of them, Tony can smell Steve all around him and feel firm muscle pressed against him from all sides. It’s a good place to be.

Other Steve wants more, swinging a leg over and straddling Tony’s waist. He seems delighted just to be so close - it’s really very endearing.

The new angle brings Tony face to face, as it were, with other Steve’s cock. It’s a pretty cock - of course it is, it’s part of Steve - but other Steve seems rather embarrassed.

“Sorry,” he says as it pushes up against Tony’s thigh.

“Don’t be,” Tony says with an entirely honest grin. Steve is nuzzling against his neck, warm hand still pressed against his own cock, and Tony is feeling magnanimous.

“Here,” Tony says, looking at other Steve, “let me.”

He reaches out to play his fingers up other Steve’s length, and other Steve gives a full-body shudder.

“You like that?” Steve asks, sounding proud. Tony explores with enthusiastic curiosity.

“Yeah,” other Steve breathes. “That’s good.”

 

* * *

 

Steve watches with intense interest: the way that Tony moves with other Steve, grinning wickedly when he runs a finger along the underside of his cock. And the way other Steve shivers whenever Tony lays a hand on him, vibrating with tension all through his body.

He likes watching more than he would have imagined. Had the thought ever crossed his mind, he would have said that the idea of Tony being with anyone else was unconscionable. But it turns out, when the other person is himself, he’s okay with it.

Steve is not quite sure what that says about him. Something about possessiveness that he’d rather not examine too closely.

Whatever the reason, he is quite content to lie back, idly pleasuring Tony and watching him with other Steve. He enjoys other Steve’s reactions, seeing how Tony explores, likes the feeling of being an outsider on a private moment.

Tony turns to him at points to check in, and he must see how much Steve is enjoying the view.

“I’m gonna…” He licks his lips and tilts his head towards other Steve. “If that’s alright with you?”

That is most definitely very alright with Steve. He lounges back on the pile of pillows and watches Tony push other Steve back onto the bed. Tony nuzzles under other Steve’s jaw, where he knows Steve is sensitive, and shifts to whisper something in other Steve’s ear.

Other Steve's eyes widen and he nods enthusiastically.

Tony leans over other Steve and runs his hands over his chest, down his sides, along the thick meat of his thighs. Tony’s eyes sparkle in the low light as he wets his lips and pushes other Steve’s legs apart, settling between them.

Tony holds eye contact with other Steve as he bends his head and swipes his tongue along the head of his cock. Steve knows from experience how heady that is: the full focus and energy of Tony Stark trained directly on you, him focused on nothing less than your total and complete pleasure.

Other Steve makes a noise like he might be dying, a guttural groan pulled from deep in his throat.

Steve finds he enjoys the sound, a kind of muscle memory of the way he’s felt with Tony so many times reflected back at him from this other version of himself. It’s like seeing himself and Tony together, like he’s outside of himself and looking in on something private. But it’s his privacy, his and Tony’s, them together but shared with another.

He notes the way other Steve’s throat works as Tony swallows him down, the way his thighs are trembling, and Steve knows it’s because he’s resisting the urge to push deeper in. He’s enjoying the pleasure, but he’s more concerned with not hurting Tony, not being too much for him.

Steve knows by now that he’s never too much for Tony. Tony loves it when he gets a bit wild, a bit out of control, when he loosens some of his inhibitions and lets go. He remembers the time he’d cracked their solid oak headboard with his bare hands while Tony was riding him and Tony had come like he was seeing the stars.

But other Steve doesn’t know that about Tony yet, so he’s reining himself in, hands bunched into fists on the sheets and a line of sweat forming across his brow.

Tony is looking up at other Steve through his lashes as he sucks him down, and Steve knows exactly how good a view that is. Tony’s mouth is sinful, always moving and so slick, but his eyes are where he is most beautiful. There’s a focus, a clarity there. When Tony looks at Steve it’s like he _sees_ him, strengths and flaws and messy humanity all at once.

A lock of hair has flopped down onto Tony’s brow and Other Steve unpeels one hand from the bedsheets and ever so gently moves it aside.

Steve smiles. Clearly this other Steve cares about Tony as much as he does. He’s just never had the experience of being with him before, and now they get to share that all together.

 

* * *

 

As focused as he is on the ample mouthful of cock he’s currently handling and the beautiful man it’s attached to, Tony is also very aware of Steve behind him.

He’s always aware of Steve: on the battlefield, in training, and at home. Steve seems so large to him, not in terms of size but in terms of presence. Steve could stand in a corner and not say a single word and Tony would still feel as if the whole room revolved around him. He’s Tony’s center.

So Tony feels the exact moment at which Steve relaxes, when he unwinds and lets go of the uncertainty he’s been hiding until now and decides that they can trust other Steve. Other Steve is with them, can be part of them, and it’s okay.

It fills Tony with an unexpected feeling of peace. He’s here, taking down a frankly hefty amount of cock into his mouth, it bumping up against the back of his throat and other Steve writhing in front of him, trying not to squeeze his arms too tight.

But he’s floating as well, in a warm, soft cocoon of love and appreciation and care that is him and Steve and their relationship. In any world, in any place, there will always be Steve and Tony and this bond between them.

Steve shifts behind him and he feels the familiar weight of big hands, calloused from work, strong but gentle, resting on his hips. He likes the way Steve’s fingers curl around his hip bones, as if Steve wants to wrap himself around Tony entirely.

Tony pulls back off other Steve for a moment and gives him a smile. Bless his heart, having Tony smile at him seems to make him blush more than having his cock sucked.

“Enjoying yourself?” Steve asks, amusement in his voice. Tony honestly isn’t sure who that question is directed to, but both he and other Steve moan out affirmatives.

“Good,” Steve says, and his hands are stroking across Tony’s shoulder blades, down his spine, around his thighs. “I like watching you,” he says quietly, and Tony feels how much that’s true.

He feels the evidence of Steve’s interest pressed hotly against his thigh. It makes his mouth water even more. He turns his head enough to raise an eyebrow at Steve, a clear challenge.

Steve huffs fondly. “Alright, alright,” he says.

Tony goes back to his task, running his tongue along the underside of other Steve’s cock, sliding his lips around the head, sucking gently and enjoying the way other Steve twitches.

He can feel Steve’s hand squeezing his ass, his fingers playing lightly over the skin, and Tony’s cock is so hard he thinks he might lose his mind if Steve doesn’t stop teasing him and let him have it.

Thankfully Steve has never been the person to deny Tony what he wants, and soon Steve’s fingers are brushing up against Tony’s hole, sparkles of pleasure zinging through his body.

Tony makes himself relax, lets Steve prepare him and open him up, drooling pleasure-dazed over other Steve’s cock. Not that other Steve seems to mind. If anything, judging from the quickening of his breath he rather likes the sight of Tony with his eyes lidded and saliva dripping down his chin.

 

* * *

 

Steve enjoys getting Tony prepped. Part of it is that he doesn’t want to cause him any pain, of course. Steve isn’t one to boast, but he knows that he’s sizeable, and he knows it takes some time for Tony to be ready to take him in.

But he also likes prepping Tony because it’s an excuse to dote on him. To appreciate every line and angle of Tony’s body, from the soft skin inside his thighs to the hard muscle of his lower back; the curve of his ass and the sharp blades of his shoulders. Every part of Tony is beautiful, and Steve gets to revel in it all.

He knows that Tony is impatient, always wanting more and harder and now, but he likes to take his time.

He watches his fingers sliding into Tony, like Tony is enveloping him, taking more of him in. He’s unnecessarily generous with the lube, partly so he doesn’t hurt Tony and partly, if he’s really honest, because he likes seeing Tony all messy. Tony doesn’t seem to mind.

He loves the way Tony stretches around him, opening so wide. He loves the way Tony feels inside, so tight and hot. And he loves the noises Tony makes, satisfied little hums and sharp intakes of breath as he gasps around other Steve’s cock.

He could do this forever, quite happily. But Tony is growing impatient, and he could never deny Tony anything he wants.

Satisfied that Tony is ready, Steve takes his cock in hand and slicks himself up. It feels good - he’s been so focused on Tony that he hasn’t been paying attention to himself - but he knows that being inside Tony will feel even better.

Tony is currently deepthroating other Steve like a champ, and Steve is absurdly proud. Tony is focused with laser intensity on his task, and other Steve has his eyes closed and his head thrown back in pleasure.

He lays a hand on the small of Tony’s back and places a kiss between his shoulder blades. Tony pulls off other Steve long enough to look round and give him a beaming smile.

“You ready?” Steve asks, stroking his back.

“Hell yeah,” Tony says, waggling his butt.

Steve can’t help but laugh. He catches other Steve’s eye and the two of them share a look, a moment where they’re both thinking the same thought: _He might be ridiculous, but dear God, do I love this man_.

When Steve slides inside Tony, it feels as good as it always does.

Tony is tight around him and so warm, but he takes care to go slow. Tony huffs like the air is being drawn out of his lungs and Steve stills, letting him adjust.

Tony has never been patient though, and soon he’s encouraging Steve in further. He hums with satisfaction and Steve thinks he can feel it all through his own body, reverberations of mutual pleasure running between the two of them.

Other Steve is watching the two of them with a distant, astonished look on his face and his dick in his hand. “God, _Tony_ ,” he says, sounding truly awed, and Tony blushes delightfully.

Steve lays a hand on Tony’s hip and pulls him close, thrusting deep into him. Steve can’t see Tony’s face from here, more’s the shame, but he can imagine the soft, blissed-out look that he gets when Steve fucks him like this.

“Good?” he asks carefully.

“Mmmmm,” Tony hums. “Exceedingly.”

Tony looks up at other Steve, and Steve knows exactly how powerful the Tony-Stark-looking-up-at-you-from-under-his-lashes magic is. Other Steve doesn’t stand a chance.

“Want to join in?” Tony asks, attempting coy but clearly enjoying himself too much for that to be convincing.

Other Steve opens his mouth and says nothing, then takes a second and nods frantically.

“Come on then,” Tony says with a wicked lilt. “My mouth is currently unoccupied.”

Steve backs off a little, taking it easy as other Steve lines up his cock with Tony’s mouth. Tony sticks his tongue out and licks enthusiastically, and other Steve bites his lip.

“Relax and enjoy yourself for once,” he instructs other Steve. He knows better than anyone that other Steve never lets himself loosen up, the feeling of responsibility and duty always there, always overriding whatever it is he wants for him.

Steve finds that he wants to give this to other Steve: the opportunity to simply _be_ for a short while, to find pleasure and contentment, away from the judgement of strangers. He gives other Steve an encouraging smile.

Other Steve moves and lets Tony take him in as well, and then Tony is stretched between the two of them, taking them both, held in place and doing so very well.

Steve strokes a hand down Tony’s back, reassuring him that they’re in this together. He thrusts slowly, leisurely, taking his time. As good as it feels for Steve, he enjoys seeing Tony feeling good even more.

When he looks up at other Steve, opposite him in front of Tony, his lips are open and his eyes are screwed shut. He looks tense, like he’s checking out. Steve reaches forward, and it’s awkward but he manages to grab other Steve’s hand and gives it a squeeze.

Other Steve’s eyes fly open and he looks at Steve, looks down at Tony, smiles shyly. Steve sees him unwind, the tension flowing out of his shoulders. His breath hitches, the same way Steve’s does when he’s close. Tony notices as well, opening his jaw wide and sucking him down with greater urgency.

“Oh gosh, _Tony_ ,” other Steve pants. “I can’t, I’m going to-”

He tries to pull back but Tony hooks an arm around his thighs and holds him in place. When he comes, he’s shaking and gasping, utterly wrung out by everything Tony’s doing to him.

Tony swallows in a way that somehow manages to convey smug delightedness, and other Steve pulls back just enough to collapse onto the bed, breathing heavily. There’s a spot of cum dribbling from the corner of Tony’s mouth, and Steve leans over him to tenderly wipe it away.

With Tony all to himself, Steve loosens his careful control and gives it to Tony hard, the way he likes. Other Steve watches them, content and smiling, and when Tony comes with a groan, other Steve is there to hold him through it.

Finally, with everyone’s needs satisfied, Steve loses himself to his own pleasure. Lights twinkle behind his eyes as he gives a final few strong thrusts into Tony and spirals into the warm abyss of pleasure.

The three of them end up entwined in one sticky, happy mess of limbs and hands and dopey smiles.

 

* * *

 

The next morning Tony is awoken by the sharp sensation of someone elbowing him in the ribs. He sits up in a flurry, ready to run off on a mission or do battle, looking around the assess the danger… and realizes that the only danger he’s in is of being squashed by two cuddly Steves, all three of the squeezed into one bed.

He smiles, lies back down, and hears a pleased murmur from his Steve as he cuddles up to him.

“Morning,” Steve mumbles.

People think that Captain America leaps out of bed in the morning, bright-eyed and bushy-tailed, ready to face the day. These people have never seen a soft, easily confused, very delicate early morning Steve.

“Good morning,” other Steve mumbles in the same tone. He readjusts his sizeable elbows. “Sorry if I woke you.”

“I’ll forgive you,” Tony says with a smile, “as this is such a nice way to wake up.”

Other Steve huffs and cuddles up to him as well.

It’s like being snuggled by two large and dozy octopuses. But more muscular and much more arousing.

The thought of coffee crosses Tony’s mind, as it always does first thing in the morning. But strong as the temptation of a hot caffeinated beverage is, the pull of a bed full of two Steves is stronger.

Tony resigns himself to the fact he’s not going anywhere this morning. He’s just going to have to stay right here.

How utterly dreadful.

 

* * *

 

By the time the three of them make it down to the lab, Steve’s finally awake. And all it took was a few episodes of snoozing, a cup of coffee, a hot shower, and a second round with Tony and other Steve to get him out of bed.

Still, he doesn't feel too bad about it. There are certainly worse ways to spend a morning.

The three of them had bumped into Clint and Hulk grabbing breakfast in the kitchen. Of course they’d told the team about other Steve’s appearance yesterday, but Hulk still seemed rather surprised by the situation - judging by the way he looked from one Steve to the other, eyes narrowed in confusion. “SPANGLES ONE AND SPANGLES TWO,” he’d eventually declared with a firm nod. “GOOD.”

Clint, on the other hand, had taken one look at Tony flanked by the two Steves and had somehow just _known_. “Oh god, you didn’t. You did, didn’t you?” He’d flapped a hand and covered his face dramatically. “My eyes! My precious virginal eyes! I’m not going to be able to stop picturing it!”

Tony had stuck his tongue out at Clint, and the two Steves had shrugged at each other. This was simply the inevitable downside to living with two former spies.

Back in the lab, the thingamajig that Tony was working on yesterday seems to be ready. At least, the gas inside the glass canister has turned to a delicate lilac color, and the box it’s hooked up to emits a cheerful ping. Tony’s reaction seems to suggest that was the aim.

“See how the antimatter transducer has been activated?” Tony waves a spanner triumphantly. “That means the decay properties of the antiquarks has been matched to our guest’s home universe.”

Steve has no idea what that means, but he sure is proud of his genius husband. He smiles encouragingly. “Great job, Tony,” he says.

He loves the way that Tony still glows whenever he compliments him. After all this time, Tony still seems a little shocked at how much Steve adores him.

When he turns to other Steve he expects him to be glad. He’s going home! They fixed it. But instead, he’s chewing at his lip in a way Steve knows means he’s worried.

 

* * *

 

“Oh,” other Steve says, making a not entirely convincing effort to smile, “that’s good. Thank you, Tony.”

Tony has learned over the last 24 hours that he can’t bear to see any version of Steve being unhappy. And he recognizes the warning signs of a Steve-Rogers-trying-to-be-stoic maneuver.

“Hey, sweetie,” he steps closer and lays a hand on other Steve’s arm and other Steve goes bright red. Whether that’s due to their physical proximity bringing back memories of last night or due to his use of the endearment, Tony couldn’t say. “What’s wrong? I thought you wanted to go home.”

Other Steve looks down at his feet, trying to shrink his huge frame down into something tiny. “I have to go home, I know that. My team will be worried, and I can’t stay here.” He fidgets. “I just.” He glances up at Tony, suddenly shy. “I’ll miss you,” he says, very quietly.

“Oh, honey.” Tony gathers other Steve up in his arms and pulls him into a hug. His Steve pats other Steve comfortingly on the back. “You want to know something?” Tony says, with the air of imparting a great secret. “Your Tony is missing you already. He’s going out of his mind without you.”

Other Steve steps back and his face scrunches up. “I’m not sure about that. I don’t think he feels the same way -”

“Trust me,” Tony says, with not a hint of doubt. “He does. There’s not a single universe in the multiverse where I don’t love you.”

Other Steve takes a deep breath and nods slowly, like he’s trying to digest the idea.

Steve is standing behind other Steve, beaming with pride. Tony is glad that at least his version of Steve knows that he is loved.

The antimatter bridge conduit device (the ABCD, he’s named it in his head, which he thinks is rather clever) pings loudly. Tony goes to check on it and sees the gaseous medium has reached peak saturation. Or, in non-scientific parlance, the gas is a lovely rosey lilac shade that means it’s ready.

He carefully sets the device up on the bench and positions other Steve next to him. “Are you going to tell him how you feel?” he asks, feigning casualness as he makes final adjustments.

“I don’t think I can keep it a secret any longer,” other Steve says, though he doesn’t sound too regretful. “After last night… I feel like it’s all over my face.”

Tony opens his mouth to make a “that’s what she said” joke but his Steve pokes him firmly in the ribs.

“It’ll be for the best,” Steve says kindly. “You two are going to be very happy together.”

Other Steve’s face goes all wobbly, like the thought is almost too much for him. He closes his eyes and nods. “Tony is worth the risk,” he says, like he’s made up his mind.

Steve reaches behind him and squeezes Tony’s hand.

“Good man,” Tony says. “Right then, let’s get you home.”

He activates the ABCD by rapping one end firmly on the tabletop (not the fanciest activation method, but highly effective) and the gas inside begins to glow.

He and Steve step back as the device pings at a higher and higher frequency, vibrating on the table with jittery motions.

Tony can see other Steve’s face, highlighted in pink by the glowing gas, a mixture of determination and curiosity playing over his features. He really is beautiful, Tony thinks.

And then, with a dramatic _ZAP_ sound, a portal opens between them. It’s like a rent in spacetime, pink sparkles dancing around the edges.

And through the portal, they can see a workshop. A workshop that looks an awful lot like the one they’re in, but this workshop has only one occupant.

Tony sees through the portal: a version of himself jumping to his feet and staring back in astonishment. The other Tony hasn’t bothered with such niceties as sleeping or showering in the last day, judging by his matted hair and the dark bags under his eyes.

“Wha?” other Tony burbles. He really is tired, bless him.

He waves cheerfully at other Tony. “Hello there! Parallel universe version of you here. I might have, umm, slightly torn a hole in spacetime trying to extract zero-point energy?”

Other Tony nods. He might be tired, but he catches up quickly. “Right, by maximizing antimatter imbalances to open a one-way exotic particle bridge? I was going to try that next week.”

“I wouldn’t,” Tony advises. “It didn’t go well. But we’ve got someone here who I guess you’ve been looking for,” he says, and steps aside to reveal other Steve.

Other Tony’s face lights up with glowing joy when he sees other Steve, like everything that seemed bleak and hopeless a second ago has turned to sunshine now because Steve is here.

Tony knows how that feels.

“Steve,” other Tony says. “You’re okay!”

“I’m fine,” other Steve confirms. “I hope you weren’t worried.”

Other Tony waves a hand, trying to suggest it was no big deal, like it it wasn’t as if he’s been obsessing and worrying every single second since other Steve disappeared. No one seems the least bit convinced by that.

“Ready to go home?” Tony asks.

Other Steve tears his eyes away from other Tony and turns to Tony and Steve. “I am,” he says. “Thank you both. For everything.” The tips of his ears go an adorable shade of red, and Tony knows exactly what he’s thinking about.

“It was most definitely our pleasure,” he says, waggling his eyebrows. Steve elbows him behind the desk.

Other Steve smiles and turns to the portal, ready to step through.

“One last thing before you go -” Tony reaches out for other Steve’s arm, grabbing his collar as he turns. He pulls other Steve in for a quick, messy kiss. The tops of other Steve’s ears go even pinker.

Through the portal, Tony sees other Tony’s eyes go wide with shock and something that looks distinctly like hope.

“Go get your man,” Tony says, and pushes him through the portal.

 

* * *

 

The portal closes behind other Steve with a loud _POP_.

And then it’s just Steve and Tony left in the lab. Everything back as it should be.

Steve slides an arm around Tony’s waist and pulls him into a hug. He reflects, not for the first time, about how lucky he is to have Tony as his husband. He knows that any version of him without a Tony to call his own would be a lonelier, emptier version.

“I hope things work out for him,” he says, contemplating the sad thought of the years other Steve had spent without Tony.

Tony takes his hand and presses a kiss to his knuckles, just above the gold band of his wedding ring.

“They will,” Tony says, not a hint of doubt in his voice. “You and I are meant to be in every universe.”


End file.
